This invention relates to presses, and more particularly, to pneumatic presses. In the prior art, presses actuated by various means, including pneumatic pistons and cylinders, have utilized punch and die sets to perform work on a work piece. Pneumatically actuated presses have generally been limited to light duty work even though it has been desirable to use pneumatic presses in other than light duty work, since the known pneumatic systems are limited in capacity. Some examples of prior art presses are illustrated in U.S. Pat. Nos. 1,038,934, 1,488,562, 2,241,794 and 3,230,812.
More recently, in patent application Ser. No. 650,926, filed Jan. 21, 1976, now U.S. Pat. No. 4,004,480, and in U.S. Pat. No. 3,690,207, I have described fluid piston actuated presses which have overcome many of the disadvantages of prior art.